Busaba Phruksaphanrat และ Naipaporn Tipmanee. (2019) Six sigma DMAIC for machine efficiency improvement in a carpet factory. <i>Songklanakarin Journal of Science and Technology</i>, <i>41</i>(4), 887-898.Busaba Phruksaphanrat และ Naipaporn Tipmanee. "Six sigma DMAIC for machine efficiency improvement in a carpet factory". Songklanakarin Journal of Science and Technology 41 (2019):887-898.Busaba Phruksaphanrat และ Naipaporn Tipmanee. Six sigma DMAIC for machine efficiency improvement in a carpet factory. Research and Development Office, Prince of Songkla University:ม.ป.ท. 2019.